Logo
Unionpedia
Communication
Get it on Google Play
New! Download Unionpedia on your Android™ device!
Download
Faster access than browser!
 

Photometry (optics)

Index Photometry (optics)

Photometry is the science of the measurement of light, in terms of its perceived brightness to the human eye. [1]

42 relations: Candela, Colorimetry, Compact fluorescent lamp, Foot-candle, Foot-lambert, Goniophotometer, Human eye, Incandescent light bulb, Infrared, Lambert (unit), Laser pointer, Light, List of light sources, Lumen (unit), Luminance, Luminosity function, Luminous flux, Luminous intensity, Measurement, Mesopic vision, Nanometre, Phot, Photodetector, Photometer, Photometria, Photometry (astronomy), Photopic vision, Point source, Radiance, Radiant energy, Radiant flux, Radiant intensity, Radiometer, Radiometry, Reflectance, Scotopic vision, Spectrometer, Steradian, Stilb (unit), Ultraviolet, Watt, Wavelength.

Candela

The candela (or; symbol: cd) is the base unit of luminous intensity in the International System of Units (SI); that is, luminous power per unit solid angle emitted by a point light source in a particular direction.

New!!: Photometry (optics) and Candela · See more »

Colorimetry

Colorimetry is "the science and technology used to quantify and describe physically the human color perception." It is similar to spectrophotometry, but is distinguished by its interest in reducing spectra to the physical correlates of color perception, most often the CIE 1931 XYZ color space tristimulus values and related quantities.

New!!: Photometry (optics) and Colorimetry · See more »

Compact fluorescent lamp

A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light, and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for incandescent bulbs.

New!!: Photometry (optics) and Compact fluorescent lamp · See more »

Foot-candle

A foot-candle (sometimes foot candle; abbreviated fc, lm/ft2, or sometimes ft-c) is a non-SI unit of illuminance or light intensity.

New!!: Photometry (optics) and Foot-candle · See more »

Foot-lambert

A foot-lambert or footlambert (fL, sometimes fl or ft-L) is a unit of luminance in United States customary units and some other unit systems.

New!!: Photometry (optics) and Foot-lambert · See more »

Goniophotometer

A Goniophotometer is a device used for measurement of the light emitted from an object at different angles.

New!!: Photometry (optics) and Goniophotometer · See more »

Human eye

The human eye is an organ which reacts to light and pressure.

New!!: Photometry (optics) and Human eye · See more »

Incandescent light bulb

An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a wire filament heated to such a high temperature that it glows with visible light (incandescence).

New!!: Photometry (optics) and Incandescent light bulb · See more »

Infrared

Infrared radiation (IR) is electromagnetic radiation (EMR) with longer wavelengths than those of visible light, and is therefore generally invisible to the human eye (although IR at wavelengths up to 1050 nm from specially pulsed lasers can be seen by humans under certain conditions). It is sometimes called infrared light.

New!!: Photometry (optics) and Infrared · See more »

Lambert (unit)

The lambert (symbol L, la or Lb) is a non-SI unit of luminance named for Johann Heinrich Lambert (1728–1777), a Swiss mathematician, physicist and astronomer.

New!!: Photometry (optics) and Lambert (unit) · See more »

Laser pointer

A laser pointer or laser pen is a small handheld device with a power source (usually a battery) and a laser diode emitting a very narrow coherent low-powered laser beam of visible light, intended to be used to highlight something of interest by illuminating it with a small bright spot of colored light.

New!!: Photometry (optics) and Laser pointer · See more »

Light

Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum.

New!!: Photometry (optics) and Light · See more »

List of light sources

This is a list of sources of light, including both natural and artificial processes that emit light.

New!!: Photometry (optics) and List of light sources · See more »

Lumen (unit)

The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the total quantity of visible light emitted by a source.

New!!: Photometry (optics) and Lumen (unit) · See more »

Luminance

Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction.

New!!: Photometry (optics) and Luminance · See more »

Luminosity function

A luminosity function or luminous efficiency function describes the average spectral sensitivity of human visual perception of brightness.

New!!: Photometry (optics) and Luminosity function · See more »

Luminous flux

In photometry, luminous flux or luminous power is the measure of the perceived power of light.

New!!: Photometry (optics) and Luminous flux · See more »

Luminous intensity

In photometry, luminous intensity is a measure of the wavelength-weighted power emitted by a light source in a particular direction per unit solid angle, based on the luminosity function, a standardized model of the sensitivity of the human eye.

New!!: Photometry (optics) and Luminous intensity · See more »

Measurement

Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or events.

New!!: Photometry (optics) and Measurement · See more »

Mesopic vision

Mesopic vision is a combination of photopic vision and scotopic vision in low but not quite dark lighting situations.

New!!: Photometry (optics) and Mesopic vision · See more »

Nanometre

The nanometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American spelling) is a unit of length in the metric system, equal to one billionth (short scale) of a metre (m).

New!!: Photometry (optics) and Nanometre · See more »

Phot

A phot (ph) is a photometric unit of illuminance, or luminous flux through an area.

New!!: Photometry (optics) and Phot · See more »

Photodetector

Photosensors or photodetectors are sensors of light or other electromagnetic energy.

New!!: Photometry (optics) and Photodetector · See more »

Photometer

A photometer, generally, is an instrument that measures light intensity or the optical properties of solutions or surfaces.

New!!: Photometry (optics) and Photometer · See more »

Photometria

Photometria is a book on the measurement of light by Johann Heinrich Lambert published in 1760.

New!!: Photometry (optics) and Photometria · See more »

Photometry (astronomy)

Photometry is a technique of astronomy concerned with measuring the flux, or intensity of an astronomical object's electromagnetic radiation.

New!!: Photometry (optics) and Photometry (astronomy) · See more »

Photopic vision

Photopic vision is the vision of the eye under well-lit conditions (luminance level 10 to 108 cd/m2).

New!!: Photometry (optics) and Photopic vision · See more »

Point source

A point source is a single identifiable localised source of something.

New!!: Photometry (optics) and Point source · See more »

Radiance

In radiometry, radiance is the radiant flux emitted, reflected, transmitted or received by a given surface, per unit solid angle per unit projected area.

New!!: Photometry (optics) and Radiance · See more »

Radiant energy

In physics, and in particular as measured by radiometry, radiant energy is the energy of electromagnetic and gravitational radiation.

New!!: Photometry (optics) and Radiant energy · See more »

Radiant flux

In radiometry, radiant flux or radiant power is the radiant energy emitted, reflected, transmitted or received, per unit time, and spectral flux or spectral power is the radiant flux per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency or of wavelength.

New!!: Photometry (optics) and Radiant flux · See more »

Radiant intensity

In radiometry, radiant intensity is the radiant flux emitted, reflected, transmitted or received, per unit solid angle, and spectral intensity is the radiant intensity per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency or of wavelength.

New!!: Photometry (optics) and Radiant intensity · See more »

Radiometer

A radiometer or roentgenometer is a device for measuring the radiant flux (power) of electromagnetic radiation.

New!!: Photometry (optics) and Radiometer · See more »

Radiometry

Radiometry is a set of techniques for measuring electromagnetic radiation, including visible light.

New!!: Photometry (optics) and Radiometry · See more »

Reflectance

Reflectance of the surface of a material is its effectiveness in reflecting radiant energy.

New!!: Photometry (optics) and Reflectance · See more »

Scotopic vision

Scotopic vision is the vision of the eye under low-light levels.

New!!: Photometry (optics) and Scotopic vision · See more »

Spectrometer

A spectrometer is a scientific instrument used to separate and measure spectral components of a physical phenomenon.

New!!: Photometry (optics) and Spectrometer · See more »

Steradian

No description.

New!!: Photometry (optics) and Steradian · See more »

Stilb (unit)

The stilb (sb) is the CGS unit of luminance for objects that are not self-luminous.

New!!: Photometry (optics) and Stilb (unit) · See more »

Ultraviolet

Ultraviolet (UV) is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.

New!!: Photometry (optics) and Ultraviolet · See more »

Watt

The watt (symbol: W) is a unit of power.

New!!: Photometry (optics) and Watt · See more »

Wavelength

In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats.

New!!: Photometry (optics) and Wavelength · See more »

Redirects here:

Photometric quantities, Photometrics.

References

[1] https://en.wikipedia.org/wiki/Photometry_(optics)

OutgoingIncoming
Hey! We are on Facebook now! »